WiFi disabling itself

[OsakaWebbie]

Recently (the last week or two) I keep discovering my Moto G4 with WiFi disabled. I haven't caught it in the act of turning off, but even if I haven't left my own home, I'll notice that that it's using cellular, and when I go to Settings, the whole WiFi functionality is in disabled mode. When I turn it back on, it reconnects to my router and works fine... until the next time it turns off on its own. I notice it perhaps once or twice a day, but I don't pay close attention, so I'm not sure how long it stays on each time or what might be causing it to turn off. Any thoughts about this?

Another issue has been going on longer (a few months) and is probably unrelated, but I'll mention it just in case there might be a relationship: At random moments when the phone is on but not being touched (e.g. I'm reading something on it or its just sitting on the desk next to me but is not asleep), it will suddenly reboot. I only see it happen about once a week or maybe even less often. There is no evidence of it happening when the phone is asleep (the apps are just where I left them), and I don't remember it happening when I was actually operating the phone - only when awake but idle. A little annoying, but I haven't worried about it so far - I'm only mentioning it here in case there is some common cause with the WiFi thing.

 

[Dannydet]

Reboot your router.
Check your recent installs on your phone.
Many times there's a rogue app that will cause reboots as mentioned.

 

[OsakaWebbie]

Reboot your router.

How could my router disable the phone's WiFi? Perhaps I didn't explain my situation clearly - I'm not talking about a lack of connection to a router, but this:

I have no problem connecting when WiFi is on. And it doesn't just happen here, but elsewhere, too.

Check your recent installs on your phone.
Many times there's a rogue app that will cause reboots as mentioned.

Is there a way to see when an app was installed (or better yet, see a list of apps in date order)? The reboot problem started long enough ago that I'm not sure I can remember what I might have installed at that time.

 

[Dannydet]

If the phone is shutting it off then it's a hardware issue with the phone.
There's really no way to pinpoint what app is causing the reboots.
Usually a disconnect from wifi is a problem with the router, so if you reboot the router it will reset anything that MAY be causing the problem.

 

[lunatic59]

If this only happens on your home network, then I'd have to agree with @Dannydet that at least the router is part of the issue.

Here's what i think are two probable scenarios. If you have wifi going to sleep when the phone sleeps, and you have a rather short lease time in your DHCP settings on your router, when you wake up the phone, it tries to reconnect using the old connection but the router has since dropped it, at which point, instead of renewing the lease, shuts itself off. However, I don't really think I've ever seen a phone do that, unless the G4 has some peculiar options for WiFi when it sleeps.

What I think is more probable is that your WiFi radio might be failing or overheating. It would certainly account for WiFi being off randomly and your phone rebooting by itself. Random reboots are usually indicative of a hardware issue. Is the phone still under warranty? YOu might consider having it replaced.

 

[OsakaWebbie]

It's not only on my home network, and not necessarily when it sleeps.

Yeah, I was afraid that the reboot issue might be a hardware problem. It didn't occur to me that the WiFi issue might be hardware also.

I bought the phone in July 2017, so unless the warranty period is unusually long, it's probably not under warranty. Phones in this price range are probably best considered commodities after they are out of warranty, but I really hoped it would last longer than this, because I have a challenge for phone shopping. I live in Japan but travel to the U.S. a lot, so I swap out the SIM card. There is surprisingly little overlap in 4G bands between the service I use in Japan (which uses DoCoMo's cell towers) and the one I use in the U.S. (T-Mobile) - the G4 was the only phone I found in either country that had any bands in common with both.

 

[lunatic59]

The only thing that bothers me is that the WiFi radio would be most stressed and hottest while you're using it and I would expect this to drop WiFi in the middle of a heavy download, not when sitting idle on a table.

 

[OsakaWebbie]

It's the restarts that happen during on-but-idle times, not the WiFi disabling. Sorry that I mentioned both issues in the same thread - I've caused confusion. The WiFi disabling happens at some time when I'm not looking.

You mentioned stress and heat - could charging cause stress to the WiFi radio? Yesterday I kept a closer eye on the WiFi status, and the only time it turned off was sometime while it was charging unattended. However, earlier today I charged it again (even though it didn't really need it yet), and the WiFi didn't switch off. Go figure.

 

[lunatic59]

Charging definitely produces heat, but you'd have to generate enough heat that you'd feel it. When charging does you phone feel warm at all?

Do you by chance have any power saving/optimization apps? Even if they came preinstalled? It really sounds like something is deliberately turning off your WiFi and keeping it off. If you go into settings>networks>WiFi>[menu]>advanced WiFi settings check to see if "keep wifi on when screen is off" is set to "yes".

 

[OsakaWebbie]

When charging does you phone feel warm at all?

No, the phone doesn't feel warm when charging, although it is in a folio case so it's less obvious. It does get warm when tethering for my PC. (In fact, that's how I know when I forget to turn off tethering when I'm done with it - I pick up the phone and notice that it's warm!)

Do you by chance have any power saving/optimization apps? Even if they came preinstalled?

Dunno. Nothing I intentionally installed or changed recently. I don't normally have power issues - when in Japan, my SIM is just for data (I have a flip phone I still like), so the battery does pretty good.

If you go into settings>networks>WiFi>[menu]>advanced WiFi settings check to see if "keep wifi on when screen is off" is set to "yes".

The path and wording is a little different, but I found it. Settings -> Wireless & networks -> Wi-Fi -> [gear-icon] (not [dots-menu] -> Advanced, which has other stuff): "Keep Wi-Fi on during sleep" is set to "Always".

Curiously, the phone has been better behaved since I reached out to you guys. It knows it is being watched by experts, I guess! Since you mentioned the idea of rogue apps, I did go through my apps and remove ones I had experimented with but weren't intending to keep. I don't remember installing any new apps around the time when the WiFi started flaking out, but maybe there was an update to a buggy new version of something - I get app updates all the time, as I assume we all do.